Portable sauna



FIG. 1 is a perspective view of a portable sauna showing my new design;

FIG. 2 is a front view of the portable sauna of FIG. 1;

FIG. 3 is a top view of the portable sauna;

FIG. 4 is a right side view of the portable sauna;

FIG. 5 is a back view of the portable sauna;

FIG. 6 is a bottom view of the portable sauna; and,

FIG. 7 is a left side view of the portable sauna.

The dashed lines are understood to represent stitching. 

The ornamental design for a portable sauna, as shown and described. 